Battery pack, charger and terminal block arrangements for cordless power tool system

ABSTRACT

A battery pack, charger, and terminal blocks for the pack, charger and a cordless power tool are provided. The pack includes battery cells disposed between end caps within a bottom housing of the pack, and a potting boat for housing pack electronics electrically connected to the cells between the end caps and disposed within a pack top housing. A pack terminal block is connected to the potting boat within the top housing. The charger and the power tool each include a terminal block for providing electrical connections between the charger/tool and the battery pack. The terminal block is configured to float side-to-side to provide displaceable movement of the terminal block within the charger housing or tool housing for aligning the battery pack terminal block therein.

PRIORITY STATEMENT

This U.S. non-provisional patent application claims priority of U.S.provisional applications 60/731,273, filed Oct. 31, 2005, and60/731,272, filed Oct. 31, 2005, the entire contents of each provisionalapplication being hereby incorporated by reference herein.

BACKGROUND

1. Field of the Invention

Example embodiments relate generally to battery pack and charger for acordless power tool system, to a terminal block for the battery pack,and to a terminal block for a cordless power tool and the batterycharger which interfaces to the battery pack terminal block.

2. Description of Related Art

Cordless products which use rechargeable batteries are prevalentthroughout the workplace as well as in the home. From housewares topower tools, rechargeable batteries are used in numerous devices.Ordinarily, nickel-cadmium (NiCd), nickel metal-hydride (NiMH) and/orLithium-ion (Li-ion) battery cells are used in these devices. Since thedevices use a plurality of battery cells, the battery cells areordinarily packaged as battery packs. These battery packs may be coupledwith the cordless devices and be secured to the device. The battery packmay be removed from the cordless device and charged in a battery chargeror charged in the cordless device itself.

One of the disadvantages associated with cordless devices is thefrequent charging of the battery pack due to power limitations of thebattery pack. The charging of the battery requires releasablydisconnecting the battery pack to the cordless device. As a result, theconnections between the battery pack and the cordless devices may weaken(deteriorate the electrically connections) and/or damage theconnections.

Terminal blocks can be provided on the battery pack and the cordlessdevice for releasably interconnecting and electrically connecting thebattery pack to the cordless device. The terminal blocks can includeconnections that prevent any lateral and longitudinal movement relativeto the each terminal block.

Moreover, the battery pack can be centered along an axis of the cordlessdevice through engagement of guide rails on the battery pack withcooperating guide rails carried by the cordless device. The battery packis then more finely centered through engagement of the tool terminalblock with the battery pack terminal block.

However, due to the frequent interconnections between the terminalblocks, blades on the terminal blocks may deteriorate or be damaged.This can cause misalignment between blades of two connected terminalblocks. This misalignment can adversely affect the mechanical andelectrical contact between the two terminal blocks.

SUMMARY

An example embodiment is directed to a battery pack having a packhousing comprised of a top housing portion and a bottom housing portion,and a plurality of battery cells disposed between a pair of end capswithin the bottom housing portion. The pack includes a potting boatdisposed within the top housing portion. The potting boat houses packelectronics that are electrically connected to the cells between the endcaps. The battery pack includes a terminal block connected to thepotting boat and disposed within the top housing portion for engaging aterminal block of an attached cordless power tool or charger.

Another example embodiment is directed to a charger having a housingcomprised of a top housing portion and a bottom housing portion. Thecharger includes an open deck cavity formed through the top and bottomhousing positions for receiving a battery pack. The charger includes apair of vertical spaced rails disposed in sides of the open deck cavityfor engaging grooves on the battery pack. The charger includes aterminal block disposed within the open deck cavity for providingelectrical connections between the charger and the battery pack. Theterminal block is configured to float side-to-side to providedisplaceable movement of the terminal block within the housing foraligning the battery pack within the charger.

Another example embodiment is directed to a cordless power tool. Thecordless power tool includes a housing comprised of a first clam-shellhalf and a second clam-shell half joined together at a longitudinalcenterline of the housing that bisects the two clam-shell halves. Thecordless power tool includes a pair of spaced guide rails disposed onthe bottom of the tool housing along opposing side edges at the housingbottom for engaging grooves of a battery pack. A terminal block isdisposed in the bottom of the housing for providing electricalcommunications between the cordless power tool and the battery pack. Theterminal block is configured to float side-to-side to providedisplaceable movement of the terminal block within the housing foraligning the battery pack with the power tool.

Another example embodiment is directed terminal block of an electricaldevice for engagement with a battery pack terminal block. The deviceterminal block includes a main body, a logic terminal centrally locatedin the main body between a single power terminal and a pair of powerterminals, and a logic terminal protector disposed below the logicterminal. A plurality of ribs is disposed on one of an underside of themain body above the logic terminal and a surface of the logic terminalprotector below the logic terminal.

Another example embodiment is directed to a system having a battery packand battery charger. The pack includes a pack housing and batteryterminal block disposed therein. The battery terminal block includes abattery logic area and a plurality of female power terminals. The packhousing includes a pair of grooves, each groove formed along oppositesides of the pack housing.

The charger includes a charger housing having a pair of verticallyspaced guide rails for slidably receiving the corresponding grooves inthe pack housing. The charger housing includes a charger terminal blockdisposed in an open cavity of the charger housing for receiving thebattery terminal block of the pack. The charger terminal block includesa logic terminal configured to mate within the battery logic area andincludes a plurality of male blade terminals for engaging the femaleterminals in the battery terminal block. The charger terminal block isdisplaceable within the open cavity so that it can move side-to-side toalign the battery terminal block relative to the charger terminal blockprior to connecting the corresponding terminal blades and logicterminals.

Another example embodiment is directed to a system having a battery packand cordless power tool. The pack includes a pack housing and a batteryterminal block disposed therein, and the battery terminal block includesa battery logic area and a plurality of female power terminals. The packhousing includes a pair of grooves, each groove formed along oppositesides of the pack housing.

The power tool includes a tool housing having a pair of spaced guiderails disposed on side edges at a bottom of the tool housing andslidably receivable in the corresponding grooves of the pack housing.The tool housing includes a tool terminal block for mating with thebattery terminal block. The tool terminal block includes a logicterminal configured to mate within the battery logic area and aplurality of male blade terminals for engaging the female terminals inthe battery terminal block. The tool terminal block is displaceablewithin the tool housing so that it can move side-to-side to align thebattery terminal block relative to the tool terminal block prior toconnecting the corresponding terminal blades and logic terminals.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention will become more apparentby describing, in detail, exemplary embodiments thereof with referenceto the attached drawings, wherein like procedures are represented bylike reference numerals, which are given by way of illustration only andthus do not limit the present invention.

FIG. 1 is a schematic view of a battery pack in accordance with anexemplary embodiment of the present invention.

FIG. 2 is a schematic view of a top housing of the battery pack inaccordance with an exemplary embodiment of the present invention.

FIG. 3 is a schematic view of the battery pack without the top housingin accordance with an exemplary embodiment of the present invention.

FIG. 4 is a schematic view of a battery cell arrangement in accordancewith an exemplary embodiment of the present invention.

FIG. 5 is a schematic view of a battery pack terminal block inaccordance with an exemplary embodiment of the present invention.

FIG. 6 is a schematic view of a terminal block in accordance with anexemplary embodiment of the present invention.

FIG. 7 is a schematic view of a charger with a terminal block inaccordance with an exemplary embodiment of the present invention.

FIG. 8 is a plan view of a bottom of a power tool with a terminal blockin accordance with an exemplary embodiment of the present invention.

FIG. 9 is a schematic view of a tool terminal block in accordance withan exemplary embodiment of the present invention.

FIG. 10 is a top view of a terminal block in accordance with anexemplary embodiment of the present invention.

FIG. 11 is a schematic view of terminal blocks interconnected inaccordance with an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

It should be noted that these figures are intended to illustrate thegeneral characteristics of method and apparatus of exemplary embodimentsof this invention, for the purpose of the description of such exemplaryembodiments herein. These drawings are not, however, to scale and maynot precisely reflect the characteristics of any given embodiment, andshould not be interpreted as defining or limiting the range of values orproperties of exemplary embodiments within the scope of this invention.The relative dimensions and size of the tool, the battery pack and thebattery charger may be reduced or exaggerated for clarity. Like numeralsare used for like and corresponding parts of the various drawings.

As used herein, power tools may be understood as a cordless power toolwith the use of light-weight portable power sources, such as lithium-ion(Li-ion) battery packs that may provide the commensurate power with itsuse. Exemplary power tools may include, but are not limited to, drills,high torque impact wrenches, single-handed metal working tools, nailers,hand planers, circular saws, jig saws, variable speed belt sanders,reciprocating saws, two handed drills such as rotary and demolitionthickness hammerdrills, routers, cut-off tools, plate joiners, drillpresses, table saws, planers, miter saws, metal working tools, chopsaws, cut-off machines, bench grinders, etc. Some of these tools maycurrently be commercially available only in a corded version, but maybecome cordless. These classifications are not intended to be inclusiveof all power tools in which exemplary embodiments of the presentinvention may be applied, but are only illustrative.

It should be appreciated by one skilled in the art that the battery packdescribed herein includes a plurality of battery cells disposed within abattery pack housing. The battery pack may be embodied as at least oneof a lithium ion (Li-ion), a nickel cadmium (NiCd), a nickel metalhydride (NiMH) and a lead-acid battery pack, for example, in terms ofthe chemistry makeup of individual cells, electrodes and electrolyte ofthe battery pack. The battery cells may be connected in series and/orparallel.

With continued reference to the figures, example embodiments pertain tointerfaces between a cordless power tool 30 and a battery pack 10, andinterfaces between a battery charger 50 and a battery pack 10. Duringthe remainder of this detailed description, it will be understood thatthe interfaces described herein may be employed in various other tools,which may be substantially identical.

FIG. 1 is a schematic view of a battery pack in accordance with anexample embodiment. The battery pack 10 includes a housing 100. Thehousing 100 is shown to include a top housing 110 and a bottom housing120 which are joined at a longitudinally extending parting line 125.Alternatively, it will be understood that the housing 100 may include apair of halves joined at a laterally extending parting line, or variousother constructions including two or more housing portions. In anexemplary embodiment, the battery pack housing 100 has an overall lengthof approximately 11 cm, an overall width of approximately 7.75 cm, andan overall height of approximately 3 cm.

The top and bottom housing 110 and 120 may each be unitarily constructedfrom a rigid plastic or other suitable material. The top and bottomhousings 110 and 120 are joined by thread-forming fasteners 132. Thethread-forming fasteners 132 pass through cooperating apertures 144and/or through the apertures 144 and screw boss portions 146 integrallyformed in the sides of each of the top and bottom housings 110 and 120.Upon assembly, the fasteners 132 thread into the screw boss portions 146of housing 100. However, it should be appreciated that the top andbottom housings 110, 120 may be attached by other means known in theart. Further, the bottom housing 120 is provided with a peripheralgroove 152 (shown in FIG. 3) extending around an upper edge portion ofthe bottom housing 120 so as to receive a corresponding mating rib 193(shown in FIG. 2) peripherally extending around the lower half of thetop housing 110.

The top housing 110 includes a slotted opening 161 in which a latch 155extends therethrough. The latch 155 is a release mechanism for releasingthe battery pack 10 from the power tool 30. An operator can release thebattery pack 10 from the power tool 30 by depressing a latch releasebutton 150. Preferably, the latch release button 150 is disposed on aback region of the pack 10. By depressing the latch release button 150,the latch 155 is urged from the “lock” position to a “release” position.In the “release” position, the latch 155 no longer obstructs a recessarea (not shown) in the tool 30. As a result, the battery pack 10 can beeasily removed from the battery receiving portion of the power tool 30by depressing the latch release button 150 disposed at the back regionof the pack 10.

The top housing 110 includes a plurality of openings 164 for receivingthread-forming fasteners (not shown) to attach a potting boat 190 (shownin FIG. 3), which will be described in detail later.

FIG. 2 is a schematic view of a top housing 110 of the battery pack inaccordance with an example embodiment. Referring to FIG. 2, the tophousing 110 includes an upper portion 175 which is slidably engageablewith a cordless power tool 30 or charger 50, and a lower portion 176. Abattery pack terminal block 200 is disposed in the upper portion 175which will be described further below. Constructing the top housing 110shape to include the upper portion 175 provides an efficient alignmentsystem between the battery pack 10 and the cordless power tool 30 duringinsertion and withdrawal. In other words, the upper portion 175 of thetop housing 110 acts to coarsely align the battery pack 10 with a toolhousing or charger housing, and reduces the tolerance stack-up to onlytwo parts. This is unlike conventional cordless interfaces which providenumerous stack-up parts (e.g., battery housings and numerous railsystems).

The top housing 110 includes a groove 180 formed in each side beneaththe guide rails 179 for slidably engaging guide rails (not shown) of acordless power tool 30 or charger 50. The groove 180 enables alignmentof guide rails on a tool (or charger) housing (not shown) so that thetool terminal block 300 directly contacts the battery terminal block200. Because the two terminal blocks 200, 300 have direct access foralignment purposes, the number of tolerance stack up parts needed foralignment may be reduced.

To facilitate insertion and releasable attachment of the battery pack 10to the cordless power tool 30, the upper portion 175 of the top housing110 includes a pair of guide rails 179, each guide rail 179 formed in aside of the top housing 110. The guide rails 179 are slidably receivedinto cooperating channels defined by rails 612, 614 (shown best in FIG.8) formed in a housing 600 of cordless power tool 30. Specifically, abottom of the tool housing 600 is constructed and arranged to receiveand secure the battery pack 10 within a battery receiving portion 202.

The guide rails 179 generally have an inverted “L-shaped” configurationand are composed an upright member 181 extending upwards from ahorizontal surface of top housing 110, and a flange member 182 extendinglaterally from and substantially perpendicular to the upright member 181as shown in FIG. 2. The laterally spaced guide rails 179 aremirror-images of each other to slidably engage and cooperate with firstand second guide channels 612, 614, respectively, of the cordless powertool 30. The flange member 182 of each guide rail 179 includes achamfered or beveled leading edge 183. The chamfered or beveled leadingedges 183 allow for easier alignment and interconnection between theguide rails 179 and the guide channels 612, 614. Openings 188 arelocated beneath the beveled edges 183 of flange 182 on each side are forsecuring a battery terminal block 200 within the top housing 110. Endsof the battery terminal block 200 slightly protrude or jut out throughthe openings 188.

The battery pack terminal block 200 is thus disposed within the upperportion 175 of the top housing 110. The battery pack terminal block 200generally includes a main body portion 210 (shown in FIG. 5) whichmatingly engage a terminal block 300 of a cordless power tool 30 orcharger 50.

The upper portion 175 includes a plurality of blade terminal openings191 for receiving corresponding terminals 512, 514, 516 (as best shownin FIG. 9) of the tool/charger terminal block 300. The blade terminalopenings 191 ensure a proper alignment therein of the blade terminals512, 514, 516 of the tool/charger terminal block 300, and prevent entryof any bent or damaged blade terminals 512, 514, 516 from engaging thebattery pack terminal block 200.

Located on a top forward surface of the bottom portion 120 near theblade terminal openings 191 are rails 189 to help facilitate theinsertion of the terminal block 300 of the cordless power tool 30 orcharger 50. In other words, the rails 189 can grossly or coarsely alignthe two terminal blocks 200, 300. Moreover, during engagement of the twoterminal blocks 200, 300, the rails 189 act to prevent displaceablemovement of the tool/charger terminal block 300, block 300 when isengaged to battery pack terminal block 200. In other words, the rails189 permit a slight tolerance (±2 mm) of displaceable movement of theattached tool/charger terminal block 300.

FIG. 3 is a schematic view of the battery pack 10 without the tophousing 110 to expose the inside of the pack 10. As shown in FIG. 3, thepack 10 includes a potting boat 190 connected to the terminal block 200.The potting boat 190 and the terminal block 200 may be joined by atongue and groove connection 177. It should be appreciated that otherconnections may be employed. The connection 177 will seal the interfacebetween the potting boat 190 and the terminal block 200 to permit packelectronics to be filled within the potting boat 190 with a pottingcompound. The potting compound also helps to mechanically restrain theterminal block 200 in position within the battery pack 10. Moreover, byconnecting the terminal block 200 to the potting boat 190, the terminalblock 200 acts as a fourth wall of the potting boat to contain thepotting material housing pack electronics in the boat 190, as comparedto when the terminal block 200 is located on top of the potting boat190. This results in a more efficient and slender construction of thepack 10.

The potting boat 190 includes openings 192 on a top surface to receivefasteners 132 so as to secure the top housing 110 to the potting boat190. In particular, the potting boat 190 and terminal block 200 fit upwithin a recessed area (not shown) within the interior of the topportion 175 of top housing 110. Referring also to FIGS. 1 and 2,fasteners 132 extend through openings 164 in the upper portion 175 toengage threaded openings 192 at the corners of the potting boat 190.This secures the potting boat 190 with attached battery pack terminalblock 200 up within top portion 175. The potting boat 190 is invertedwithin top portion 175, such that the pack electronics restrained withinthe potting boat 190 by the potting compound are facing downward towardthe bottom housing 120.

Referring to FIG. 4, and also with reference to FIG. 3, the potting boat190 is spaced from the end caps 196 containing the cells 195 therebetween. Clearance between the potting boat 190 in the top housing 110and the end caps 196 in the bottom housing 120 is provided by aplurality of raised projections 197 which are formed along the top sidesof the end caps 196. These projections 197 provide proper alignmentbetween components in the top and bottom housings 110, 120 as thehousings 110, 120 are clamped together.

The end caps 196 serve as a backbone to support all of the batteryinternal components, including the battery cells 195. The internalbattery pack structural arrangement between the top and bottom housingsis described in further detail in co-pending U.S. patent applicationSer. No. 11/552,847 to Phillips et al., filed Oct. 25, 2006 and entitled“BATTERY PACK AND INTERNAL COMPONENT ARRANGEMENT WITHIN THE BATTERY PACKFOR CORDLESS POWER TOOL SYSTEM”, the entire contents of which is herebyincorporated by reference herein.

Although not shown in FIGS. 3 and 4, the cells 195 are electricallyconnected to pack electronics within potting boat 190 via a connectorattached to a wiring harness of the potting boat 190. The connectorattaches to a connector 198 that is integrated within each end cap 196.Power terminal leads (not shown) from the cells 195 are alsoelectrically connected to the battery pack terminal block 200, as isknown.

FIGS. 5 and 6 are schematic views of the battery pack terminal block200. Referring to FIG. 5, the battery pack terminal block 200 isdisposed within the top housing 110, and constructed and arranged toengage a terminal block 300 disposed within a cordless power tool 30 orcharger 50. Accordingly, electrical communication is provided betweenthe battery pack terminal block 200 and the tool/charger terminal block300.

The battery pack terminal block 200 includes a battery logic areaportion 215 adapted to receive a logic terminal of a tool/chargerterminal block 300. A plurality of contacts 211 are provided on theinterior surface of the battery logic area portion 215 to engage with aplurality of contacts (not shown) on the tool/charger terminal block300. The plurality of contacts 211 may be formed on an upper surfaceand/or a lower surface of the battery logic area portion 215, as shownbest in FIG. 6.

The battery pack terminal block 200 includes a plurality of tongues 212,214 and 216 to conduct positive and negative charges. Tongue 212 engageswith and is adapted to receive a male blade terminal 512 of thetool/charger terminal block 300, tongue 214 engages with and is adaptedto receive male blade terminal 514, and tongue 216 engages with and isadapted to receive the male blade terminal 516 of the tool/chargerterminal block 300 (shown in FIG. 9). The tongues 212, 214 and 216 maythus otherwise be understood as female terminals of terminal block 200.The tongues 212, 214 and 216 may be made from conductive metal, forexample, such as phosphor bronze and/or beryllium copper, so as toconduct positive and negative charges. The tongues 212, 214, 216 alsoensure a tight engagement with the terminal blades 512, 514, 516,respectively. In an example, tongue 212 is a positive terminal andtongues 214 and 216 are negative terminals

The battery pack terminal block 200 includes an aperture 220 forreceiving a logic terminal protector 520 of an attached tool 50 orcharger 30 (shown best in FIG. 9). The aperture 220 should have the samedimensions as the logic terminal protector 520 so as to provide a tightengagement. The aperture 220 may also act as a centering and guidingmeans for the terminal blocks 200, 300.

With reference to FIGS. 5 and 9, the battery pack terminal block 200includes a pair of laterally spaced protrusions 225. The protrusions 225are adapted to slidably engage with an interior side of a pair oflaterally spaced grooves 530 of the tool/charger terminal block 300. Thelaterally spaced protrusions 225 help to establish more precisealignment with the tool/charger terminal block 300. The leading edge ofgrooves 530 may be chamfered or beveled to facilitate the protrusions225 slidably engaging the laterally spaced grooves 530.

Reference should be made to FIGS. 7-11 for the following descriptiondirected to a terminal block for the cordless power tool 30 or charger50. FIG. 7 is a schematic view of a charger 50 with a terminal block 300in accordance with an exemplary embodiment. Referring to FIG. 7, thecharger 50 includes a charger housing 410. The charger housing 410includes a top housing 413 and a bottom housing 415 joined at alongitudinally extending parting line shown at 417. The charger housing410 includes LED indicators 412 to indicate the status of charge in anattached battery pack. Although the exemplary embodiment illustratesthree (3) LED indicators, it should be appreciated that more or lessthan three (3) indicators may be employed, depending on the functionsdesired. The charger housing 410 includes an open deck cavity 425 forvertically receiving a battery pack (not shown).

To facilitate releasable insertion of the battery pack 10 into thecharger housing 410, the open deck cavity 425 includes a pair of grooves427 at lateral sides of the open deck cavity 425. The pair of grooves427 are adapted to receive cooperating guide rails 179 on the batterypack 10. Accordingly, insertion and removal of the battery pack 10to/from the charger 30 may thereby be facilitated by the groove-railengagement.

The battery charger terminal block 300 is disposed within the open deckcavity 425. The terminal block 300 provides the logic and powerterminals connections between the charger 50 and battery pack 10, suchas electrical communication between the charger 50 and battery pack 10.The terminal block 300 includes power terminals 512, 514, 516 and logicterminals 511 (as best shown in FIG. 9). In this example, the powerterminals include one positive power terminal (male blade terminal 512)and two negative power terminals (male blade terminals 514, 516), oneeach for charge and discharge operations.

In FIG. 7, an arrow 305 is shown to illustrate the relative side-to-sidedisplacement of the terminal block 300. The terminal block 300 can float(side-to-side) to align the terminals of the charger 50 while insertingthe battery pack 10 into the charger 50. In an example, the displaceablemovement can be ±2 mm in either direction. It should be appreciated thatmore or less side-to-side displacement of the terminal block 300 ispossible depending on the design of the tool/charger.

The displaceable movement enables precise alignment to occur before anymating of any terminals (power or logic) of the terminal blocks 200,300. Moreover, the displaceable movement of the tool/charger terminalblocks 200, 300 reduces the tight tolerance necessary to align the logicand power terminals because the alignment occurs before mating of anyterminals. As discussed above, the rails 189 on the top housing 110 ofpack 100 establishes the amount of displacement movement, as the twoterminal blocks 200, 300 are connected.

FIG. 8 is a plan view of a bottom of a power cordless power tool 30 inaccordance with an exemplary embodiment. For illustrative purposes, thepower tool 30 is an electric power drill/driver; however, it should beappreciated that other power tools such as discussed above may beapplicable. The cordless power tool 30 has a housing 602 that can bemolded from a suitable plastic material, such as polyethylene,polypropylene, and/or polyurethane. In an example, the power toolhousing 602 is injection molded having two halves portions 602A, 602B.The two halve portions 602A, 602B are secured together in a conventionalmanner using mechanical fasteners (not shown), such as screws.

A first guide rail 612 is formed along the right edge of housing 602 atthe bottom of the cordless power tool 30, and a second guide rail 614 isformed along the left edge of housing 602. The first and second guiderails 612, 614 are designed to cooperatively mate with grooves of abattery pack. For example, specifically, the battery pack 10 in FIG. 2includes corresponding grooves 180 to slidably engage and interlock withthe first and second guide rails 612, 614, as previously discussed.

A chamfered or beveled edge 617 is formed at the leading edge of theguide rails 612, 614 to facilitate the alignment and interlockingbetween the grooves 180 on the battery pack 10 and the guide rails 612,614 of tool housing 602.

The arrow 305 in FIG. 8 is to illustrate the relative side-to-sidedisplacement of the tool terminal block 300. The tool terminal block 300can float side-to-side to align the terminals of the cordless power tool30 with the battery pack 10 prior to inserting the battery pack 10 intothe cordless power tool 30. The displaceable movement may be ±2 mm ineither direction or other appropriate distance depending on the designof the tool 30. The displaceable movement enables more precise alignmentto be achieved between pack and tool terminal block 200, 300.

To further facilitate attachment of the battery pack 10 to the cordlesspower tool 30, a recess 619 is provided at the end of the cordless powertool 30. The recess 619 is conventional in construction and operationand engages a corresponding latch (not shown) of the battery pack 10upon insertion. Removal of the battery pack 10 is thereby preventeduntil a spring bias of a latch is overcome in a conventional manner,insofar as the example embodiments are concerned.

FIG. 9 is a schematic view in detail of a terminal block 300 inaccordance with an example embodiment. The terminal block 300 is useablein an electrical device such as the above discussed cordless power tool30 or charger 50. The terminal block 300 may be molded from any suitableplastic material, such as glass-reinforced PBT, glass-filled nylon,polyethylene, polypropylene, and/or polyurethane. However, othermaterials may be used to manufacture the terminal block 300. Theterminal block 300 engages the battery terminal block 200 (as shown bestin FIG. 11).

Referring to FIG. 9, a main body 501 of the terminal block 300 includesa top plate 502 and back plate 505. The top plate 502 is fittinglyattached to a surface on an electrical device such as a cordless powertool 30 or charger 50. The attachment of the top plate 502 to thecordless power tool 30 or charger 50 may be attached by, for example, agroove-guide arrangement, adhesive, fasteners or any other means. Theback plate 505 includes the electrical connections of the logic andpower terminals via wires (not shown).

The terminal block 300 includes a logic terminal portion 510 and powerterminals (male blade terminals 512, 514 and 516). The logic terminalportion 510 is configured to be inserted into the battery logic areaportion 215 of the battery pack terminal block 200. The logic terminalportion 510 includes a plurality of contacts 511 to engage with contacts211 (as shown in FIG. 5) on the battery pack terminal block 200 forelectrical communications. In an example, contacts 511 are provided oneither or both surfaces of logic terminal portion 510, as shown in FIG.5. The electrical communications functions of logic terminal portion 510are generally known in the art and are not be discussed in detailherein. There are seven contacts 511 shown on the logic terminal 510 ofFIG. 9; however, it should be appreciated that a different number ofcontacts 511 may be employed depending on the functions desired.

The power terminal 512 is embodied as a positive male terminal blade andadapted to engage with a contact tongue 212 (female terminal) in thebattery terminal block 200. Power terminals 514 and 516 are negativemale terminal blades and adapted to engage with contact tongues 214 and216 (female blades), respectively, in the battery terminal block 200.The power terminal 514 is employed for a charging function and the powerterminal 516 is employed for a discharging function. It should beappreciated that the charging/discharging functions may be reversed inthese two terminals 514, 516.

Referring to FIG. 10, the power terminal 516 is slightly offset (orlonger) than the power terminal 514 or the power terminal 512 so thatterminal 516 initially contacts i.e., (mates first with) tongue 216 onthe battery pack 10. In other words, the charge negative (ground) powerterminal 516 is offset or extended forward of the other power terminals514, 516 so as to mate first and precede mating of the other powerterminals 512, 514. The offset negative power terminal 516 establishes aground contact to act as a safety mechanism for electric shock and/oravoid static shock in the cordless power tool 30 or charger 50 and/orbattery pack 10. Moreover, providing a longer or offset negative powerterminal 516 allows the use of the same geometry as the dischargenegative and positive terminals, while enabling the negative terminalblade to mate first before the other terminals. This establishes a solidground before the other circuits are connected.

Referring back to FIG. 9, terminal block 300 includes a logic terminalprotector 520 below the logic terminal 510. The logic terminal protector520 engages with the aperture 220 (as shown in FIG. 5) in the batterypack terminal block 200. The logic terminal protector 520 may beembodied as a longitudinally elongated platform below the logic terminal510 to act as a guiding means for insertion to the battery pack terminalblock 200. The logic terminal protector 520 has generally the same widthas the logic terminal 510, and may shield the logic terminal 510 fromdebris and contamination. Further, during impact of the tool 30 (orcharger 50), the logic terminal protector 520 may protect the logicterminal 510 from damage, and/or be used as a ‘lock-out’ scheme toprevent mating between other non-standard or improper battery packs.

The main body 501 includes a plurality of ribs 507 for strengthening thestructure of the terminal block 300. The plurality of ribs 507 may alsoact as a “stop” element when interconnecting the terminal block 300 withthe battery pack terminal block 200. The ribs 507 may be disposed on anunderside of the top plate 505, formed on a surface of the logicterminal protector 520, or both, as shown in FIG. 9

The terminal block 300 includes a pair of laterally spaced grooves 530.The laterally spaced grooves 530 are assembled to retain the terminalblock 300 within the cordless power tool 30 or charger 50. The terminalblock 300 includes an extension 519 on the face of the terminal block.The extension 519 is a structural element which acts as a ‘stop’ memberfor the terminal block 300.

The terminal block 300 includes a pair of apertures 540. Each apertureholds a coil spring 545 therein. The springs 545 may engage with thesurface of flange member rail 182 located on the battery pack 10 so asto absorb the impact when the cordless power tool 30 (or charger 50)engages the battery pack 10. In other words, the springs 545 may act asa shock absorber to reduce impact. The springs 245 may also provide aresistance when the tool and the battery are connected (e.g., thesprings 245 affect not only a mechanical engagement/disengagement, butalso causes the electrical connection between battery pack and the toolto be safely interrupted). Moreover, the springs 245 may aid in batterypack ejection. When the user depresses the latch button, the springs 245effectively push the battery pack clear of the terminals, and make iteasier for the user to remove the battery pack from the tool.

FIG. 11 is a schematic view of the terminal blocks 200, 300interconnected in accordance with an exemplary embodiment. Referring toFIG. 11, a battery terminal block 200 and a terminal block 300 areinterconnected to illustrate the mechanical and electrical connections.Terminal block 300 can be part of the housing of power tool 30 orcharger 50. Thus, this terminal block 300 in general forms part of anelectrical device that is to be engaged to a battery pack such as pack10.

The battery pack terminal block 200 includes a female positive terminal(tongue 212), a first female negative terminal (tongue 214) and a secondfemale negative terminal (tongue 216). The female positive terminal 212is adapted to engage male blade terminal 512 of the terminal block 300.The first female negative terminal 214 is adapted to engage with maleblade terminal 514 of the terminal block 300, and the second femalenegative terminal 216 is adapted to engage with male blade terminal 516of the tool/charger terminal block 300.

As the battery pack 10 is inserted into the cordless power tool 30 orcharger 50, the alignment of battery pack terminals and tool/chargerterminals occur in two stages. In the first stage, the guide rails 179of the battery pack 10 are loosely or coarsely engaged in the matingguide rails 612, 614 of the tool housing 602. In order to facilitate thecooperative engagement of the rails, the leading edges of rails 179 arebeveled or chamfered 183 (shown best in FIG. 2). Moreover, the leadingedges of rails 612, 614 are also beveled or chamfered (shown at 617 inFIG. 8).

In the second stage, which occurs after the battery pack 10 has traveleda relative distance into the a housing of the electrical device (i.e.,tool housing 602 or charger housing open cavity 425), the tool terminalblock 300, which includes laterally spaced grooves 530 (shown in FIG.9), engage guide rails 189 (FIG. 2) positioned on the top surface of thebottom portion 176 on the top housing 110 of battery pack 10. The rails189 ensure proper alignment with the grooves 530 (see FIGS. 9 and 11)for centering the terminal block 300 with the battery pack terminalblock 200, and providing the displaceable distance for the terminalblock 300.

The exemplary embodiments being thus described, it will be obvious thatthe same may be varied in many ways. Such variations are not to beregarded as departure from the exemplary embodiments, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

1. A battery pack, comprising: a pack housing including a top housingportion and a bottom housing portion; a plurality of battery cellsdisposed between a pair of end caps within the bottom housing portion; apotting boat filled with a potting compound, the potting boat disposedwithin the top housing portion, the potting boat housing packelectronics that are electrically connected to the cells between the endcaps; and a terminal block connected to the potting boat and disposedwithin the top housing portion for engaging a terminal block of anattached cordless power tool or charger.
 2. The battery pack accordingto claim 1, wherein the top and bottom housing portions each havingintegrally formed screw boss portions that align with each other whenthe two portions are placed together.
 3. The battery pack according toclaim 1, wherein the top housing portion includes a plurality ofopenings for receiving thread-forming fasteners to attach the pottingboat within a recessed area of the top housing portion.
 4. The batterypack according to claim 1, wherein the top housing portion includes apair of guide rails, each guide rail formed in a side of the top housingportion for slidably receiving cooperating guide rails of an attachedcordless power tool or charger.
 5. The battery pack according to claim4, wherein each guide rail is an inverted L-shaped member composed of anupright member extending upwards and a flange member extending laterallyfrom and substantially perpendicular to the upright member.
 6. Thebattery pack according to claim 5, wherein the flange member includes abeveled leading edge for engagement of the guide rails.
 7. The batterypack according to claim 1, wherein the terminal block is electricallyand/or physically connected to the potting boat.
 8. The battery packaccording to claim 7, wherein the terminal block is physically connectedto the potting boat by a tongue-and-groove connection.
 9. The batterypack according to claim 1, wherein the terminal block further comprises:a battery logic area portion adapted to receive a logic connection froman attached tool or charger; and a plurality of tongues configured toreceive blade terminals of a terminal block in an attached cordlesspower tool or charger, so as to provide power from the pack to theattached power tool or to receive charge current from an attachedcharger.
 10. The battery pack according to claim 9, wherein the batterylogic area portion includes a plurality of terminal contacts provided onan interior surface thereof.
 11. The battery pack according to claim 10,wherein the plurality of terminal contacts are disposed on an uppersurface of the battery logic area portion.
 12. The battery packaccording to claim 11, wherein the plurality of terminal contacts aredisposed on a lower surface of the battery logic area portion.
 13. Thebattery pack according to claim 9, wherein the plurality of tongues arepower terminals.
 14. The battery pack according to claim 9, wherein theplurality of tongues are embodied as three female power terminals, apositive power terminal, a negative charge terminal and a negativedischarge terminal.
 15. The battery pack according to claim 9, whereinthe terminal block further comprises an aperture for receiving a logicterminal protector from the attached tool or charger.
 16. The batterypack according to claim 9, wherein the terminal block further comprisesa pair of laterally spaced protrusion rails for slidably engaging a pairof corresponding laterally spaced rails on the attached tool or charger.17. A system, comprising: a battery pack having a pack housing and abattery terminal block disposed therein, the battery terminal blockincluding a battery logic area and a plurality of female powerterminals, the pack housing having a pair of grooves, each groove formedalong opposite sides of the pack housing; and a battery chargerincluding a charger housing having a pair of vertically spaced guiderails for slidably receiving the corresponding grooves in the packhousing, the charger housing including a charger terminal block disposedin an open cavity of the charger housing for receiving the batteryterminal block of the pack, the charger terminal block including a logicterminal configured to mate within the battery logic area and includinga plurality of male blade terminals for engaging the female terminals inthe battery terminal block, wherein the charger terminal block isdisplaceable within the open cavity so that it can move side-to-side toalign the battery terminal block relative to the charger terminal blockprior to connecting the corresponding terminal blades and logicterminals.
 18. The system of claim 17, wherein the charger terminalblock is displaceable ±2 mm in either direction.
 19. The battery packaccording to claim 1, further comprising a potting material located inthe potting boat.
 20. The battery pack according to claim 19, whereinthe terminal block is located and configured to contain the pottingmaterial in the potting boat.